The presented invention is related to the renovation of a kind of clipboard structure especially referring to an improved clip structure of clipboard to avoid usage of rivets in assembly work.
As clipboard are greatly diversified, FIG. 1 to FIG. 3 illustrate a kind of conventional clipboard comprising the major elements of a board (1), a supporting base (2), a clamping element (3), a pivotal axle (4) and a torsional spring (5). For assembly, a clamping member is made by combination of supporting base (2), clamping element (3), pivvotal axle (4) and torsional spring (5) and for riveting the clamping member on the board (1), rivets (6) are inserted through holes (201) (202).
Another kind of conventional clipboard being generally used as shown in FIG. 4 and FIG. 5 is mainly consisted of the elements of a board (7), a supporting base (8), a clamping element (9), a pivotal axle (10) and a torsional spring (11). At the rear side of supporting base (8) and clamping element (9), a curved roll-up portion exists. By virtue of pivotal axle (10) and spring (11), the supporting base (8) and clamping element (9) are pivotally connected into a similar hinge-typed clipboard. On the supporting base (8), two holes (801) (802) permit rivets (12) (13) inserting through to fix the supporting base (8) on the board (7). On the former conventional clipboard mentioned above, the applicant already presented improvement method and were awarded with U.S. Pat. No. 4,628,572. The presenting invention is aimed at the latter, the hinge-typed clipboard, for improvement. The assembly work of conventional clipboard as shown in FIG. 4 is very troublesome. As the supporting base (8) and clamping element (9) are installed in parallel, if the clamping member completed after combination of supporting base (8), clamping element (9), pivotal axle (10) and torsional springcouples with board (7), the clamping element (9) will cover up fixing holes (801) (802) on supporting base (8) causing inconvenience of riveting for rivets (12) (13) and if supporting base (8) and board (7) are riveted first and then combined with other elements, it will be very hard to install spring (11) and pivotal axle (10). In case of slight carelessness, the riveting of board (7) by means of rivets (12) (13) will break the board to be salvaged. In view of above-mentioned shortcomings, the applicant devoted himself to continuous study for improvement of such hinge-type clipboard in succession to the award of U.S. Pat. No. 4,628,572 so as to identically avoid using rivets, for coupling with board so that clipboard's manufacturing facility cost can be lowered and assembly safety upgrade.